Bonded sputtering target and methods of manufacture

Abstract

Methods for manufacturing sputtering target assemblies by bonding target materials to backing plates using metals and alloys in powder form to achieve substantially 100% bonding at temperatures achieved in a vacuum hot press.

1 . A method for manufacturing a sputtering target assembly comprising the steps of:
 providing a metallic backing plate having a first surface;   providing a metallic target material having a first surface;   providing a metallic powder;   interposing a pre-determined amount of metallic powder at a pre-determined thickness of from about 30 μm to about 1000 μm between the first surface of the target material and the first surface of the backing plate to achieve an assembly; and   subjecting the assembly to a predetermined pressure of from about 0.5 to about 2 ksi and predetermined temperature adequate to soften the powder and substantially uniformly bond the backing plate to the target material.   
   
   
       2 . The method of  claim 1 , wherein the assembly is subjected to a vacuum hot press. 
   
   
       3 . The method of  claim 2 , wherein the pressure is maintained at a pressure of about 2 ksi. 
   
   
       4 . The method of  claim 1 , wherein the metallic powder is a metal alloy powder. 
   
   
       5 . The method of  claim 1 , wherein the metallic powder is selected from the group consisting of aluminum powder and copper powder. 
   
   
       6 . The method of  claim 1 , wherein the metallic powder further comprises a dopant. 
   
   
       7 . The method of  claim 6 , wherein the dopant is a zinc powder. 
   
   
       8 . The method of  claim 1 , wherein the backing plate is substantially 100% bonded to the target material. 
   
   
       9 . The method of  claim 1 , wherein the powder has a grain size of from about 1 μm to about 100 μm. 
   
   
       10 . The method of  claim 1 , wherein the first surface of the target material and/or the first surface of the backing plate are treated to achieve a surface roughness of from about 150 Ra to about 250 Ra. 
   
   
       11 . The method of  claim 1 , wherein the metallic powder is selected from the group consisting of: aluminum metallic powder and aluminum alloy powder; said backing plate is made from aluminum; and the target material is selected from the group consisting of: tungsten, titanium, tantalum, copper, nickel, cobalt, chromium and aluminum. 
   
   
       12 . The method of  claim 1 , wherein the metallic powder is selected from the group consisting of: copper metallic powder and copper alloy powder; said backing plate is made from copper; and the target material is selected from the group consisting of: tungsten, titanium, tantalum, copper, nickel, cobalt, chromium and aluminum. 
   
   
       13 . The method of  claim 11 , wherein the assembly is maintained at a temperature in the range of from about 550° C. to about 650° C. for a duration of from about 1 to about 5 hours. 
   
   
       14 . The method of  claim 12 , wherein the assembly is maintained at a temperature in the range of from about 960° C. to about 1050° C. for a duration of from about 1 to about 5 hours. 
   
   
       15 . A sputtering target assembly made according to the method of  claim 1 . 
   
   
       16 . A sputtering target assembly made according to the method of  claim 11 . 
   
   
       17 . A sputtering target assembly made according to the method of  claim 12 . 
   
   
       18 . A plasma discharge assembly comprising a sputtering target made according to the method of  claim 1 . 
   
   
       19 . A plasma discharge assembly comprising a sputtering target made according to the method of  claim 11 . 
   
   
       20 . A plasma discharge assembly comprising a sputtering target made according to the method of  claim 12 .